I have tried with a focus finder but with spectacles I found it quite desperate. I couldn´t find the grain or to get a view of the photo to know where I am pointing at. Some areas in the photo (like eyes in a portrait in the negative) are sharp but some areas are out of focus due to short depth of field (the blurry background). Should I point at some lighter areas or the darker areas, at the moment I don´t see what I am focusing on...all blackness. Or a very bright light from the enlarger, not good for eyes to stare at it. Perhaps something is wrong with the mirror of the finder, or I don´t know how to use it correctly. I corrected the lens for my eyesight (a sharp line in the middle). Is there any other way? These finders are pretty expensive, 80 euros, don´t want to buy a new one just to check if this old one is good, or damaged. Magnifying glass costs 2 euros, does someone use that? I guess this is "The Question of the Month!" I have some other questions in store just in case this doesn´t win any prize.